(i put a file so it makes more sence) Assignment: The Arms of a Sea Star Exploration

Data Table 1: Arm Lengths of Sea Stars at Particular Years

Sample Number
Year 1
Year 50
Year 100
1 57 cm 62 cm 75 cm
2 62 cm 74 cm 77 cm
3 75 cm 77 cm 80 cm
4 78 cm 80 cm 80 cm
5 82 cm 81 cm 81 cm
6 88 cm 83 cm 83 cm
7 90 cm 88 cm 85 cm
8 95 cm 89 cm 88 cm
9 105 cm 90 cm 88 cm
10 110 cm 92 cm 90 cm
11 110 cm 95 cm 90 cm

Frequency Table 1: Frequency of Sea Star Sizes within Specific Ranges

Size Range
(in cm) Number of Organisms
Year 1 Number of Organisms
Year 50 Number of Organisms
Year 100
51–60 1
61–70 1
71–80 2
81–90
91–100
101–110

Size Frequency of Sea Stars, Year 1
7

6

5

4

3

2

1

0
51–60 61–70 71–80 81–90 91–100 101–110
Intervals (cm)

Size Frequency of Sea Stars, Year 1

7

6

5

4

3

2

1

0
51–60 61–70 71–80 81–90 91–100 101–110
Intervals (cm)

Size Frequency of Sea Stars, Year 50

7

6

5

4

3

2

1

0
51–60 61–70 71–80 81–90 91–100 101–110

Intervals (cm)

Size Frequency of Sea Stars, Year 100

7

6

5

4

3

2

1

0
51–60 61–70 71–80 81–90 91–100 101–110

Intervals (cm)

Questions

1. What change do you see over the 100-year period?

2. Suggest one reason why this change might have occurred.

3. If this population continued for the next 100 years with no changes in arm length, what could you say about these sea stars?